Marine depth sounder



FIG. 1 is a front perspective view of a marine depth sounder showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is a front perspective view of another embodiment of our new design of FIGS. 1-7;

FIG. 9 is a front elevational view thereof;

FIG. 10 is a right side elevational view thereof;

FIG. 11 is a rear elevational view thereof;

FIG. 12 is a left side elevational view thereof;

FIG. 13 is a top plan view thereof;

FIG. 14 is a bottom plan view thereof. 

The ornamental design for a marine depth sounder, substantially as shown and described. 